Introducing Queuing Protocol Adapters

Message queuing is a method by which a process can exchange or pass data using an interface to a system-managed message queue. Messages can vary in length and can be assigned different types or uses.

A message queue can be created by one process and used by multiple processes that read and/or write messages to the queue. For example, a server process can read messages from and write messages to a queue created for client processes. The message type can be used to associate a message with a particular client process although all messages are in the same queue.

An architecture for distributed systems is based on reliable message queuing. Messages are queued asynchronously between applications and systems.

The benefits of a message queuing system are:

• Multiple providers can post messages to a queue.
• Multiple message consumers can be attached to a single queue.
• The queuing infrastructure ensures messages are delivered only once.
• Messages can be submitted to a queue even when the message consumer(s) are not running or are unreachable.
• Multiple posters/readers ensure scalability.
• Systems that can make queues persistent provide reliability.
• Because producers and consumers are not interconnected, abstraction is provided (similar to a loosely coupled pipes and filters architecture).